newbie01.others wrote:Bill and Ben are brothers the sum of their ages is equal to 4 times Bob's age who is half as old as Bridget. The average age of the 4 children is 8. Write this as an equation, then solve it.

Then Bob is b/2. Bill and Ben can be "L" and "N" -- from the last letters of their names -- and then L + N = 4(b/2) = 2b. The average is the total divided by 4. See what this gives you. (P.S.: I don't think you can find Bill's and Ben's ages; you can only find Bridget's and Bob's. You don't have enough information to find the other two.)